Cut

Diamonds

Shape

Cut

Color

Clarity

Carat Weight

Certification

Care

The cut of a diamond is the main ingredient in determining how much brilliance and fire that diamond will have. There is a strict range of proportions that a diamond's cut has to meet in order for that diamond to exude maximum brilliance and fire it is capable of. Although different jewelers have different perception of what ideal proportions are, there are certain ranges which are accepted as ideal by all. Generally, in order for these ideal proportions to be met, there is a greater weight loss than if the diamond was to be cut to retain the maximum weight, therefore better cut diamonds cost more money.

There is no one particular measurement which dictates a diamond grading but rather it is a combination of factors that determine the cut grade. The main factors that are considered are depth percentage, table percentage, polish grade and symmetry grade and minor factors include pavilion angles, crown angles, girdle thickness etc. The description below for depth percentage and table percentage is only for round brilliant diamonds.

Depth percentage is the total depth, table-to-culet, of a round brilliant diamond divided by its average diameter. It is very important for the diamond to have its depth percentage be in a certain range otherwise one of the two cases occur:

Too Shallow: Light is lost from the bottom of the diamond causing light to leak out and lose its brilliance.

Too Deep: Light leaks from the side of the diamonds causing the diamond to appear dull and dark.

Cut Determines Brilliance

Determining a diamond's cut grade, however, goes beyond simple measurements of width and depth. Using an optical measuring device, a three-dimensional model is created to determine the diamond's proportions and angles. The interrelations between these various dimensions will greatly affect how light reacts once it enters and how it behaves once it exits; by using sophisticated computer modeling, it is possible to trace light behavior and measure its levels of brightness , fire and scintillation - the face-up appearance.

Diamond Anatomy

Diameter: The width of the diamond as measured through the girdle.

Table: The largest facet of a gemstone.

Crown: The top portion of a diamond extending from the girdle to the table.

Girdle: The intersection of the crown and pavilion which defines the perimeter of the diamond.

Pavilion: The bottom portion of a diamond, extending from the girdle to the culet.

Culet: The facet at the tip of a gemstone. The preferred culet is not visible with the unaided eye (graded "none" or "small").

Depth: The height of a gemstone measured from the culet to the table.

Polish and symmetry Affect Sparkle

Symmetry is the evenness between corresponding parts of a stone. This is important in maximizing the brilliance and fire of a diamond. Some of the symmetry components are misaligned facets, misshapen facets, out-of-round girdle outlines, table not parallel to girdle or wavy girdle. When choosing a diamond look for a diamond with good, very good or excellent grade on the certification

Congregation of the exactness of the cutting details, the execution of the design and the polish quality make up the polish grade. It is imperative to have good polish in order for the diamond to have maximum brilliance, fire and scintillation. Some of the polish components are bearding, scratches, polish lines, nicks and pits.

GemsNY Diamond Proportions Guideline

GemsNY maintains extremely stringent guidelines for acceptable cut grades. All diamonds we offer must fall into our stringent cut guidelines, the ones which do not are not offered on our website.

GemsNY Cut Grading Guidelines

We have tried our best to keep our cut grades in line with the three major laboratories: GIA, AGSL and EGL. This is done to ensure that we are consistent with the cut grades widely used in the jewelry market. Here below are the cut specifications we used for GemsNY to assign the cut grades for rounds and princess cuts.

ROUNDS

	TABLE	DEPTH	POLISH	SYMMETRY	FLUROSENCE

IDEAL PLUS	53-57	58.0-62.4	X, VG	X,VG	ALL

IDEAL	53-60	57.5-63.5	X, VG	X,VG	ALL

VG	52-65	56.5-64.9	X,VG,G	X,VG,G	ALL

GOOD	51-68	55.5-67.0	X,VG,G	X,VG,G	ALL

FAIR	ALL	ALL	ALL	ALL	ALL

PRINCESS CUT

	TABLE	DEPTH	POLISH	SYMMETRY	FLUROSENCE	L/W RATIO

IDEAL PLUS	65-70	65-70	X, VG, G	X,VG,G	ALL	1.00-1.05

IDEAL	63-77	64-77	X, VG, G	X,VG,G	ALL	1.00-1.05

VG	61-80	62-80	X, VG, G	X,VG,G	ALL	1.00-1.10

GOOD	60-85	60-84	X,VG,G	X,VG,G	ALL	ALL

FAIR	ALL	ALL	ALL	ALL	ALL	ALL

So What Is The Best Cut Grade For You?

It is important to remember that the cut grade is the most important factor in the amount of brilliance, scintillation and fire a diamond has. However to what extent? The difference between an ideal cut diamond and very good exists but it is minor. For individuals who are looking for the best they should only consider our ideal plus or the ideal cut. However, the very good and the good cut offer excellent value for the money and still offer very good scintillation and brilliance in a diamond.

• So for the idealist, stick with our ideal plus or the ideal cut grade only.

• For people looking for good value, consider purchasing very good or good cut diamonds. With little loss in brilliance and scintillation these diamonds offer the best value.